The invention concerns an external mirror arrangement (i.e., a vehicle mirror assembly) for use on a commercial vehicle, and more particularly concerns an external mirror arrangement in which a mirror is held in place by a holder releasably coupled to a tie-bar.
Conventional external mirror arrangements for trucks include a holder extending from and fastened to the side of the truck body. The holder is commonly a U-shaped bracket equipped with a lower and an upper, horizontally running support arm. The bracket and the free ends thereof are swingably linked to the vehicle body so as to pivot about a vertical axis. One or more external mirrors are installed on the vertically running bottom section of the U-shaped bracket. The mirrors may be, for instance, one lightly curved convex main mirror and a strongly curved convex wide angle mirror.
A basic problem with these conventional commercial external arrangements is that, because of the relatively large dimensioning and the correspondingly heavy weight of the external mirror, it is difficult to install the holder so as to have great stability and to be vibration-free.
In order to achieve an improvement in this matter, it is common to use a tie-bar support to additionally stabilize the holder. This tie-bar support is coupled on one end to the mounting arm at an external point situated far removed from the swivelable fixation point. The tie-bar support is swingably attached to the vehicle body about one half meter behind the point where the mirror holder has been installed. Thus, with the original support arm of the mirror holder coupled to the tie-bar, a rigid triangular structural reinforcement is formed, whereby the mirror holder is stabilized.
In certain situations, the mirror holder must be folded in to the vehicle body, for instance, when the vehicle must be driven through a very narrow passage, or the truck must be laid up for a long period. By means of this folding back, the mirror is protected from damage.
Additionally, it must also be possible that the mirror holder can deflect inward when contact might be made with trucks coming the other way.
In order to meet the above stated problems, the coupling between the tie-bar and the corresponding support arm is made to be releasable. When the coupling is released, the added support for the holder is removed and the holder can swing inward toward the body.
Known releasable couplings between the tie-bar and the support arm are often heavy and troublesome to recouple. Moreover, the hinged attachment of the tie-bar to its respective body attachment is generally made in such a way that the tie-bar falls downward and remains hanging in a vertical position after release.